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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Utility Stock Splits: Signaling Motive Versus Liquidity Motive

Miranda, Maria Mercedes 20 May 2005 (has links)
Despite the rich literature on theories of stock splits, studies have omitted public utility firms from their analysis and only analyzed split by industrial firms when examining managerial motives for splitting their stock. I examine the liquidity-marketability hypothesis, which states that stock splits enhance the attractiveness of shares to individual investors and increase trading volume by adjusting prices to an optimum trading range. Changes in the regulatory process, resulting from EPACT, have opened a window of opportunity for the study and comparison of the two traditional motives for splitting stock --signaling versus liquidity-marketability motives. Public electric utility firms provide a clean testing ground for these two non-mutually exclusive theories as liquidity/marketability hypothesis should dominate before the enactment of the EPACT since the conventional signaling theory of common stock splits should not apply given the low levels of information asymmetry in regulated utility companies. In the post-EPACT period, however, the signaling effect is expected to play a more dominant role. Based on both univariate and multivariate analyses, my results are consistent with the hypothesis posed. For the pre-EPACT period, liquidity motive seems to predominate in explaining the abnormal announcement return of utility stock splits. On the other hand, the results support the signaling motive as a leading explanation of abnormal returns in the post-EPACT period.
2

Flexibility Enhancement with Vibration: Acute and Long-Term

Sands, William A., McNeal, Jeni R., Stone, Michael H., Russell, Elizabeth M., Jemni, Monem 01 April 2006 (has links)
Introduction: The most popular method of stretching is static stretching. Vibration may provide a means of enhancing range of motion beyond that of static stretching alone. Purpose: This study sought to observe the effects of vibration on static stretching to determine whether vibration-aided static stretching could enhance range of motion acquisition more than static stretching alone in the forward split position. Methods: Ten highly trained male volunteer gymnasts were randomly assigned to experimental (N = 5) and control (N = 5) groups. The test was a forward split with the rear knee flexed to prevent pelvic misalignment. Height of the anterior iliac spine of the pelvis was measured at the lowest split position. Athletes stretched forward and rearward legs to the point of discomfort for 10 s followed by 5 s of rest, repeated four times on each leg and split position (4 min total). The experimental group stretched with the device turned on; the control group stretched with the device turned off. A pretest was followed by an acute phase posttest, then a second posttest measurement was performed following 4 wk of treatment. Difference scores were analyzed. Results: The acute phase showed dramatic increases in forward split flexibility for both legs (P < 0.05), whereas the long-term test showed a statistically significant increase in range of motion on the right rear leg split only (P < 0.05). Effect sizes indicated large effects in all cases. Conclusion: This study showed that vibration can be a promising means of increasing range of motion beyond that obtained with static stretching in highly trained male gymnasts.
3

An Analysis Of Stock Splits In The Istanbul Stock Exchange

Yilmaz, Isil Sevilay 01 October 2003 (has links) (PDF)
The primary purpose of this study is to test the validity of the trading range hypothesis as a basis for stock split decisions of Turkish companies. In the first part, the liquidity effects of stock splits on Turkish stocks are examined. Second, the optimal trading ranges for different-sized firms and firms with different investor bases are determined. Finally, the main empirical question of the study is analyzed by testing whether or not Turkish firms whose share prices rise above their optimal trading ranges are more likely to split their stock compared to firms whose share prices are at or below their optimal trading ranges. The empirical findings about the level of liquidity indicate that there is a slight decline in liquidity in the post-split periods. Analysis of the relationship between firm characteristics and share prices shows that firm size has a positive effect on share prices. The effect of investor base on share prices could not be identified. Finally, the estimation of the logit model utilized in the study to determine the probability of firms to split does not reveal any statistically significant result.
4

Stock splits in confliction with the economic irrelevance of shares outstanding : An event study on the Stockholm Stock Exchange

Rahaman, K.M. Abdur, Lipponen, Lasse January 2012 (has links)
A survey is conducted through an event study on the Stockholm Stock Exchange based on 119 historical stocks splits with a split factor of at least two, for the years between 1997 and 2012. This study has tested if there is an increase in return variance and systematic risk followed by a stock split. This is a quantitative study with the deductive approach and the positivistic epistemological standpoint. By matching 8925 squared daily returns for 75 days of pre- and post- split data, the sample of stock splits showed an increased return variance 0.515 of the matched squared daily returns, this number is significant at the 1% level in our binomial z-statistics. If the returns are compared on a 15 week interval instead of 75 days, the change in variance disappears; this confirms Dubofsky (1991) findings. When 52 weeks of pre- and post- split data is used, there is an increased variance in a proportion if 0.55 of the 6186 matched observations, this proportion is far greater than our daily sample and tells us that there is a long term effect on the return variance. The systematic risk measured as beta derived from the CAPM, did not show any increase in any of the three different time periods (75days, 16weeks and 52 weeks); the results confirms Wiggins (1992) findings; beta changes are just illusory.  The results suggest that there is an average increase in returns variance in the short and long term after a stock split, that confirms some existing studies by Ohlson and Penman (1985) and Dubofsky (1991). The increase in returns variance can be viewed as the management’s success of signaling the market, enhancing liquidity and reducing information asymmetry without any additional cost of capital. Our findings also contradict the theory of economic irrelevance of shares outstanding. This study is expanding Ohlson and Penman (1985) and Dubofsky (1991) studies, on a European stock market.
5

Shear strength of timber beams with end splits

Das, Shanta 27 July 2012 (has links)
Timber beams with end splits were investigated in this study to determine their shear strength. Two conditions were considered: a) Group 1 had supports located near the ends with the portion of the beam extending beyond the support, and b) Group 2 had supports located right at the end of the beam subjected to a horizontal split at approximately mid height. In Group 1, seventeen beams were tested under static loading and four were tested in fatigue. In Group 2, nineteen beams were tested under static loading and four under fatigue. In Group 1, eight beams under static loading failed in shear. In Group 2, all beams under static loading failed in shear. Group 1 and Group 2 beams under static load produced average shear strength values of 4.93 MPa and 4.49 MPa, respectively. During fatigue tests, Group 1 sustained more cycles than beams in Group 2.
6

Neighbourhoods of Phylogenetic Trees: Exact and Asymptotic Counts

de Jong, Jamie Victoria January 2015 (has links)
A central theme in phylogenetics is the reconstruction and analysis of evolutionary trees from a given set of data. To determine the optimal search methods for the reconstruction of trees, it is crucial to understand the size and structure of neighbourhoods of trees under tree rearrangement operations. The diameter and size of the immediate neighbourhood of a tree has been well-studied, however little is known about the number of trees at distance two, three or (more generally) k from a given tree. In this thesis we explore previous results on the size of these neighbourhoods under common tree rearrangement operations (NNI, SPR and TBR). We obtain new results concerning the number of trees at distance k from a given tree under the Robinson-Foulds (RF) metric and the Nearest Neighbour Interchange (NNI) operation, and the number of trees at distance two from a given tree under the Subtree Prune and Regraft (SPR) operation. We also obtain an exact count for the number of pairs of binary phylogenetic trees that share a first RF or NNI neighbour.
7

Shear strength of timber beams with end splits

Das, Shanta 27 July 2012 (has links)
Timber beams with end splits were investigated in this study to determine their shear strength. Two conditions were considered: a) Group 1 had supports located near the ends with the portion of the beam extending beyond the support, and b) Group 2 had supports located right at the end of the beam subjected to a horizontal split at approximately mid height. In Group 1, seventeen beams were tested under static loading and four were tested in fatigue. In Group 2, nineteen beams were tested under static loading and four under fatigue. In Group 1, eight beams under static loading failed in shear. In Group 2, all beams under static loading failed in shear. Group 1 and Group 2 beams under static load produced average shear strength values of 4.93 MPa and 4.49 MPa, respectively. During fatigue tests, Group 1 sustained more cycles than beams in Group 2.
8

Localised splitting criteria for classification and regression trees

A.Bremner@murdoch.edu.au, Alexandra Bremner January 2004 (has links)
This thesis presents a modification of existing entropy-based splitting criteria for classification and regression trees. Trees are typically grown using splitting criteria that choose optimal splits without taking future splits into account. This thesis examines localised splitting criteria that are based on local averaging in regression trees or local proportions in classification trees. The use of a localised criterion is motivated by the fact that future splits result in leaves that contain local observations, and hence local deviances provide a better approximation of the deviance of the fully grown tree. While most recent research has focussed on tree-averaging techniques that are aimed at taking a moderately successful splitting criterion and improving its predictive power, this thesis concentrates on improving the splitting criterion. Use of a localised splitting criterion captures local structures and enables later splits to capitalise on the placement of earlier splits when growing a tree. Using the localised splitting criterion results in much simpler trees for pure interaction data (data with no main effects) and can produce trees with fewer errors and lower residual mean deviances than those produced using a global splitting criterion when applied to real data sets with strong interaction effects. The superiority of the localised splitting criterion can persist when multiple trees are grown and averaged using simple methods. Although a single tree grown using the localised splitting criterion can outperform tree averaging using the global criterion, generally improvements in predictive performance are achieved by utilising the localised splitting criterion's property of detecting local discontinuities and averaging over sets of trees grown by placing splits where the deviance is locally minimal. Predictive performance improves further when the degree of localisation of the splitting criterion is randomly selected and weighted randomisation is used with locally minimal deviances to produce sets of trees to average over. Although state of the art methods quickly average very large numbers of trees, thus making the performance of the splitting criterion less critical, predictive performance when the localised criterion is used in bagging indicates that different splitting methods warrant investigation. The localised splitting criterion is most useful for growing one tree or a small number of trees to examine structure in the data. Structurally different trees can be obtained by simply splitting the data where the localised splitting criterion is locally optimal.
9

Alterações da solução do solo e resposta do arroz irrigado ao manejo da irrigação e da adubação nitrogenada / Soil solution changes and rice crop response as affected by irrigation and nitrogen management

Borin, José Bernardo Moraes January 2014 (has links)
Extensas áreas de produção de arroz irrigado podem ser afetadas pela escassez de água durante o ciclo da cultura, dependendo das precipitações pluviais e do gerenciamento dos mananciais hídricos pelo produtor. A irrigação intermitente é uma alternativa para a otimização do uso da água pela lavoura. Entretanto, esse manejo altera a dinâmica e disponibilidade de nutrientes na solução do solo, podendo afetar também a cultura. O objetivo deste trabalho foi avaliar a eletroquímica e a dinâmica de nutrientes na solução do solo, assim como a resposta do arroz ao parcelamento da adubação nitrogenada, em diferentes sistemas de irrigação. O experimento foi conduzido no campo, no ano agrícola de 2012/13, em um Gleissolo, na Estação Experimental do Arroz (EEA) do Instituto Rio Grandense do Arroz (IRGA), em Cachoeirinha/RS. Os tratamentos testados foram: irrigação contínua e irrigação intermitente com uma e duas supressões no estágio vegetativo. Nas subparcelas, o manejo de aplicação de N constou de 0 kg ha-1 e 150 kg ha-1 em duas e três vezes. A eletroquímica é afetada pelos sistemas de irrigação e influenciam a dinâmica e disponibilidade dos nutrientes na solução do solo. Na irrigação contínua a disponibilidade dos nutrientes é maior em relação às irrigações intermitentes. Embora a biomassa e o acúmulo do nitrogênio sejam afetados, a produtividade não diferenciou entre os sistemas de irrigação e o manejo de adubação nitrogenada. A intermitência pode ser utilizada como uma ferramenta para melhorar a eficiência de utilização do nitrogênio pela cultura do arroz irrigado. / Large areas of irrigated rice production can be affected by water scarcity during the crop cycle, depending on rainfall and management of water sources by farmer. Intermitent irrigation is an alternative to the optimization of water use by the crop. However, this management modifies the nutrient dynamics and availability in the soil solution and may also affect the crop. The objective of this study was to evaluate the electrochemical and nutrient dynamics in the soil solution, as well as the response of rice to the split of nitrogen fertilization under different irrigation systems. The experiment was conducted under field conditions in the 2012/13 agricultural season, on an Albaqualf soil in the Rice Experiment Station of Instituto Rio Grandense do Arroz (IRGA), in Cachoeirinha/RS. The treatments tested were: continuous flooding and intermittent irrigation with one and two dry cycles in the vegetative stage. Subplots consisted of nitrogen application of 0 kg ha-1 and 150 kg ha-1 in two and three splits. The soil solution electrochemistry is affected by irrigation systems and influence the nutrients dynamics and availability. In continuous flooding, nutrients availability is greater compared to intermittent irrigation. Although biomass and nitrogen accumulation are affected, grain yield did not differ between the irrigation systems and nitrogen fertilization management. The intermittent irrigation can be used as a tool to improve the nitrogen use efficiency by irrigated rice.
10

Alterações da solução do solo e resposta do arroz irrigado ao manejo da irrigação e da adubação nitrogenada / Soil solution changes and rice crop response as affected by irrigation and nitrogen management

Borin, José Bernardo Moraes January 2014 (has links)
Extensas áreas de produção de arroz irrigado podem ser afetadas pela escassez de água durante o ciclo da cultura, dependendo das precipitações pluviais e do gerenciamento dos mananciais hídricos pelo produtor. A irrigação intermitente é uma alternativa para a otimização do uso da água pela lavoura. Entretanto, esse manejo altera a dinâmica e disponibilidade de nutrientes na solução do solo, podendo afetar também a cultura. O objetivo deste trabalho foi avaliar a eletroquímica e a dinâmica de nutrientes na solução do solo, assim como a resposta do arroz ao parcelamento da adubação nitrogenada, em diferentes sistemas de irrigação. O experimento foi conduzido no campo, no ano agrícola de 2012/13, em um Gleissolo, na Estação Experimental do Arroz (EEA) do Instituto Rio Grandense do Arroz (IRGA), em Cachoeirinha/RS. Os tratamentos testados foram: irrigação contínua e irrigação intermitente com uma e duas supressões no estágio vegetativo. Nas subparcelas, o manejo de aplicação de N constou de 0 kg ha-1 e 150 kg ha-1 em duas e três vezes. A eletroquímica é afetada pelos sistemas de irrigação e influenciam a dinâmica e disponibilidade dos nutrientes na solução do solo. Na irrigação contínua a disponibilidade dos nutrientes é maior em relação às irrigações intermitentes. Embora a biomassa e o acúmulo do nitrogênio sejam afetados, a produtividade não diferenciou entre os sistemas de irrigação e o manejo de adubação nitrogenada. A intermitência pode ser utilizada como uma ferramenta para melhorar a eficiência de utilização do nitrogênio pela cultura do arroz irrigado. / Large areas of irrigated rice production can be affected by water scarcity during the crop cycle, depending on rainfall and management of water sources by farmer. Intermitent irrigation is an alternative to the optimization of water use by the crop. However, this management modifies the nutrient dynamics and availability in the soil solution and may also affect the crop. The objective of this study was to evaluate the electrochemical and nutrient dynamics in the soil solution, as well as the response of rice to the split of nitrogen fertilization under different irrigation systems. The experiment was conducted under field conditions in the 2012/13 agricultural season, on an Albaqualf soil in the Rice Experiment Station of Instituto Rio Grandense do Arroz (IRGA), in Cachoeirinha/RS. The treatments tested were: continuous flooding and intermittent irrigation with one and two dry cycles in the vegetative stage. Subplots consisted of nitrogen application of 0 kg ha-1 and 150 kg ha-1 in two and three splits. The soil solution electrochemistry is affected by irrigation systems and influence the nutrients dynamics and availability. In continuous flooding, nutrients availability is greater compared to intermittent irrigation. Although biomass and nitrogen accumulation are affected, grain yield did not differ between the irrigation systems and nitrogen fertilization management. The intermittent irrigation can be used as a tool to improve the nitrogen use efficiency by irrigated rice.

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